Text and Data Mining valid from 2018-07-28
Received: 16 May 2018
Accepted: 18 July 2018
First Online: 28 July 2018
Ethics approval and consent to participate
: Our hospital’s institutional review board (IRB) reviewed and approved this study. Since it was a retrospective study, the need for informed consent was waived.
: Not applicable.
: The authors declare that they have no competing interests.
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